We are currently testing the evaluation for just that purpose. We don't want to purchase a number of copies to find out it does not work as we intend to use it. Does the evaluation not have the full functionality (PGPDesktop10.2.1MP3.dmg)?

This has been an issue ever since entoruage supported EWS, which is https web dav, PGP deoesnt have a proxy that will work with that secure connection. You can use IMAP w/ exchange and PGP should be able to proxy those messages like it does with Apple Mail.